Quantum coherent energy transport in the Fenna–Matthews–Olson complex at low temperature

• DOI: 10.1073/pnas.2212630119
• Publication Date: 2022-11-28T22:14:31Z
• Authors: Hong-Guang Duan; Ajay Jha; Lipeng Chen; Vandana Tiwari; Richard J. Cogdell; Khuram Ashraf; Valentyn I. Prokh...; Michael Thorwart; R. J. Dwayne Miller
• Keywords: Cold Temperature; Physical Phenomena; Chlorophyll; Physical Sciences; Temperature; Electronics; 7. Clean energy; ddc:

In the primary step of natural light harvesting, solar photon energy is captured in a photoexcited electron–hole pair, or an exciton, chlorophyll. Its conversion to chemical potential occurs special pair reaction center, which reached by downhill ultrafast excited-state transport through network chromophores. Being inherently quantum, could principle occur via matter wave, with vast implications for efficiency. How long wave remains coherent determined intensity exciton disturbed noisy biological environment. The stronger this is, electronic coupling between chromophores must be overcome fluctuations and phase shifts. current consensus that under physiological conditions, quantum coherence vanishes on 10-fs time scale, rendering it irrelevant observed picosecond transfer. Yet, at low-enough temperature, should present. Here, we reveal onset longer-lived extremely low temperatures ∼20 K. Using two-dimensional spectroscopy, determine times Fenna–Matthew–Olson complex over extensive temperature range. At 20 K, persists out 200 fs (close antenna) marginally up 500 center. It decays markedly faster modest increases become above 150 fragile can separated from robust vibrational coherence, using rigorous theoretical analysis. We believe generic principle, harvesting becomes against otherwise effects.